WASHINGTON — Republican are already wielding Sen. Bob Menendez's corruption trial against his fellow Democrats, pressuring senators to say if they will vote to evict him in the event of a conviction and laying the groundwork to seize the seat if he is found guilty.

In a campaign launched this week, just as Menendez's bribery trial began in Newark, the GOP pressed vulnerable Senate Democrats to say whether they will vote to expel Menendez if he is convicted this fall.

"If he is convicted, Democrats need to make it clear to the American people that our government will not stand for corruption, especially not for political gain," read talking points that the Republican National Committee blasted out to allies earlier this week, and obtained by the Inquirer.

The RNC also launched an online ad showing Democrats in 2008, including then-Senator Barack Obama, calling for Alaska Republican Ted Stevens to step down after he was convicted on corruption charges. (The conviction was later overturned due to prosecutorial misconduct.)

Potentially at stake is a reliably Democratic Senate seat at a time when Republicans have a narrow two-vote majority, and could use any extra margin to advance their agenda. If Menendez is convicted and forced from office before mid-January, Gov. Christie would appoint a replacement — presumably naming a fellow Republican to the seat.

But Menendez would not have to resign after a conviction and expelling him would require 67 Senate votes, meaning that at least 15 Democrats would have to agree to kick him out — all while knowing it would hand his seat to the GOP. If they can drag the process out, a Democrat, Phil Murphy, is favored to win New Jersey's gubernatorial election this fall and might be in position to name Menendez's replacement, if the senator is still in office when Christie's term runs out.

Stevens, the Alaska Republican Senator, was convicted in October 2008 and lost his November reelection bid, but continued serving until his term ended the following January.

Menendez says it won't come to that — he has vowed to be vindicated at trial and intends to seek, and win, another term in office next year.

The Senate hasn't expelled a member since shortly after the Civil War, though some lawmakers resigned once it became clear they were about to be booted. Among them was another New Jerseyan, Harrison Williams, who quit in 1982 after the ethics committee recommended expelling him for his conviction on multiple corruption charges related to the Abscam scandal.

If Menendez is found guilty, Republicans plan to push vulnerable Democrats to act fast. "Are Democrats really going to let a convicted felon stay in the Senate?" the GOP digital ad asks.

So far, the pressure hasn't yielded results. Several Democrats facing tough reelections next year have said they either aren't following the trial closely or that they'll deal with the next step once there is an actual verdict.

"We all believe in the presumption of innocence in this country, and Sen. Menendez is fighting very hard," Democrats' Senate leader, Chuck Schumer, told reporters this week. "And we respect that greatly."

Menendez missed his first significant vote of the fall Thursday, as the Senate voted overwhelmingly to approve a package that included aid for areas hit by Hurricane Harvey, funding to keep the government running and a critical increase in the federal borrowing limit.

The trial resumes in Newark on Monday.