FILE - This June 23, 2014 file photo shows Internal Revenue Service Commissioner John Koskinen testifying under subpoena before the House Oversight Committee as lawmakers continue to probe whether tea party groups were targeted by the IRS on Capitol Hill in Washington. How much difference will it make if Republicans win the Senate majority on Nov. 4, joining the GOP-run House against a Democratic White House? Republicans say a GOP-led Senate would join the House in conducting investigations into political matters such as the killing of Americans in Benghazi, Libya, in 2012, the Internal Revenue Serviceâ€™s scrutiny of conservative groups, and perhaps a failed law enforcement program called Operation Fast and Furious. (AP Photo/J. Scott Applewhite)
FILE - This March 2, 2014 file photo shows demonstrators lying on Pennsylvania Avenue in front of the White House in Washington to protest against the proposed Keystone XL oil pipeline. How much difference will it make if Republicans win the Senate majority on Nov. 4, joining the GOP-run House against a Democratic White House? Some GOP goals, such as approving the Keystone XL oil pipeline or removing a tax on medical devices, might gain enough Democratic support to make a presidential veto politically difficult. (AP Photo/Manuel Balce Ceneta, File)
WASHINGTON — How much difference will it make if Republicans win the Senate majority on Nov. 4, joining the GOP-run House against a Democratic White House?
Congress' persistent gridlock is due largely, but not entirely, to the current power split in the two chambers. But even if Republicans add Senate control to their safe House majority, big legislative roadblocks will remain.
President Barack Obama still can veto legislation.
Should Democrats lose six or more Senate seats, ceding the majority, they can use the power of the filibuster to thwart dozens of GOP initiatives. Republicans have employed this tactic from the minority side.
In the House, House Republicans' deep philosophical divisions will remain. That will further complicate effort by Speaker John Boehner, R-Ohio, to pass bills without help from Democrats, who generally demand significant concessions.
In short, conservatives who see Republican control of both houses of Congress as the path to repealing the health law, slashing regulations and other priorities probably will be disappointed.
"I think the country will face two more years of gridlock," said Democrat Ted Strickland of Ohio, a former congressman and governor who now is president of the Washington-based Center for American Progress Action Fund.
At least three Republican senators — Marco Rubio of Florida, Ted Cruz of Texas and Rand Paul of Kentucky — are considering running for president in 2016. If the GOP controls the Senate after Election Day, Strickland said, it's hard to imagine "there not being a fight breaking out within the Republican family."
Some Republicans are more optimistic. But even they say that if Republicans are in charge on Capitol Hill, they may have to play down conservatives' expectations and settle for symbolic victories that highlight their differences with Democrats.
"They have to have an agenda and have to perform," said GOP Rep. Jack Kingston of Georgia, who is retiring after 22 years in the House. The party's conservative base, he said, is tired of fiery rhetoric yielding scant results.
Republican senators, Kingston said, must be able to tell voters that "we did tax reform, we did welfare reform, we did spending reform, or something that shows that there were Republican fingerprints" at government's highest levels.
Obama probably would veto such measures, Kingston acknowledged.
But making Obama do so will show the difference between the parties, Kingston said, and "that helps build the case why you need a Republican president." If nothing else, Kingston said, Republicans must force Obama to sign or veto a bill to repeal his 2010 health care overhaul, a GOP priority that Senate Democrats have blocked for years.
Obama certainly would veto that effort, but he would be powerless to stop several other initiatives.
Republicans say a GOP-led Senate would join the House in conducting investigations into political matters such as the killing of Americans in Benghazi, Libya, in 2012, the Internal Revenue Service's scrutiny of conservative groups, and perhaps a failed law enforcement program called Operation Fast and Furious.
Also, a Republican Senate could block many, if not all, of Obama's nominations to federal courts and administration jobs that require confirmation.
One Republican goal calls for packing spending bills with legislative maneuvers, known as riders, to force various policy changes.
Kentucky Sen. Mitch McConnell, poised to become majority leader if he wins re-election and his party takes over the Senate, outlined his thoughts in a secretly recorded speech to conservatives.
"No money can be spent to do this or to do that," McConnell told a June gathering sponsored by the billionaire Koch brothers, Charles and David. "We're going to go after them on health care, on financial services, on the Environmental Protection Agency, across the board."
The strategy would elevate long-running philosophical feuds between Republicans and Democrats. Democrats could use a veto or filibuster to block such bills, but that also might block spending items popular with many Americans.
Some GOP goals, such as approving the Keystone XL oil pipeline or removing a tax on medical devices, might gain enough Democratic support to make a presidential veto politically difficult.
Special rules would allow Republicans to pass a major budget bill with only 51 Senate votes. There's talk of using the tactic to try to repeal major pieces of the health law, although the president could veto it.
Repeated vetoes or Senate filibusters might make Democrats look like obstructionists, the label they long have pinned on Republicans. But many Democrats say they would welcome a Republican push for long-stalled legislation they believe most Americans would reject.
For instance, House Republicans repeatedly have voted for deep spending cuts and major changes in Medicare, knowing a Democratic-run Senate would block them and prevent intense public scrutiny. A Republican-controlled Senate, however, would feel pressured to endorse the House plan and send it to Obama's desk.
"Public beware," said Rep. Chris Van Hollen of Maryland, the House Budget Committee's top Democrat. "It's one thing to lay out a budget in abstract. It's another thing to impose it on the country."
But Michael Needham, who heads the conservative Heritage Action for America, said House and Senate majorities would give Republicans "a new tool set to show the differences in the parties" heading into the 2016 presidential campaign. Instead of House Republicans expressing their budget priorities by shutting down the government, as they did last year, "this lets you do more," Needham said.
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