By Richard Cowan and David Morgan
WASHINGTON (Reuters) - Republicans' refusal to consider any Supreme Court nominee by President Barack Obama this year could jeopardize the party's control of the Senate, as Democrats use the standoff to challenge vulnerable opponents in an election year.
Congressional leaders met with Obama at the White House on Tuesday about replacing recently deceased Justice Antonin Scalia, and Senate Republican Leader Mitch McConnell's stance opposing any nomination by Obama. Neither side gave ground.
The showdown over the issue is already being used by Democrats to target Republican senators in states including Ohio, Wisconsin, Illinois, New Hampshire and Pennsylvania, even though elections are not until November.
The Democrats have two goals. One is opening a new line of attack on Republicans in states that tend to vote Democratic in presidential election years. The other is chipping away at McConnell's position, which may be hard to maintain over time.
The Democrats' strategy will not work, said Republicans, who maintain the Supreme Court showdown actually helps them in some races and that other issues are much more important.
Voters worry more about economic and national security issues than the Supreme Court, Tom Ridge, former Republican governor of Pennsylvania, said in an interview. The court fight "may have an impact, but at best, I think it's marginal."
The issue has a long way to play out. Obama has yet to name a nominee. Also, the Supreme Court has not yet deadlocked 4-4 since Scalia's death on a high-profile issue, so there has been no stalemate to test the public's reaction.
But by haranguing vulnerable incumbents, such as Illinois Republican Mark Kirk, Democrats hope to convince swing voters that stone-walling on any Obama nominee is a dereliction of duty. Faced with this attack, Kirk last week broke ranks with McConnell and said hearings should be held on a nominee.
His possible general election opponent, Democratic Representative Tammy Duckworth, told Reuters she has hammered away at Kirk on the Senate confirmation process. "He would not have said anything if I had not pushed so hard," she said.
In Ohio and Pennsylvania, three-quarters of those polled said the Senate should at least see whom Obama nominates before deciding whether or not to confirm the nominee, according to Public Policy Polling surveys conducted Feb. 19-21.
TOOMEY'S STANCE STUDIED
Former Pennsylvania Democratic Governor Ed Rendell told Reuters the Supreme Court battle will be trouble for Republicans. "This will bring into dramatic focus, with crystal clarity, the importance of the presidential election concerning the Supreme Court," Rendell said.
Liberal activist group Moveon.org last week sponsored a 30-second cable television spot urging Senate Republicans to "Do your job" and consider an Obama appointee.
At the same time, conservative group Judicial Crisis Network launched a 30-second video thanking Senator Patrick Toomey, who supports McConnell's position, for "letting the people decide" on replacing Scalia.
Republicans must defend 24 Senate seats in November. Democrats have only 10 to defend.
Senator Rob Portman, a first-term Republican who faces a tough re-election in Ohio, has also sided with McConnell.
Republican Senator Ron Johnson of Wisconsin, who was swept into office in 2010 by the Tea Party movement, is running 11 points behind Democrat Russ Feingold, the former senator he beat six years ago, a Marquette Law School Poll last week showed.
To win, analysts said, Johnson must garner support from a different, presidential-year electorate that is likely to be younger, racially more diverse and with a potentially greater interest in moving forward with a Supreme Court nominee.
So far the court debate has helped Johnson solidify support among Republicans, two-thirds of whom support McConnell's stand.
(Additional reporting by Susan Cornwell; editing by Kevin Drawbaugh and Richard Chang)