Congressional Democrats, back Monday from the summer recess, are urging Republicans to take up a House-passed bill to expand background checks for firearm purchases.

House and Senate Democratic leaders wrote to President Trump to insist that his “personal intervention is needed” to help usher background check legislation through the GOP-led Senate.

Democrats also planned a 3 p.m. press conference in the Capitol Monday to demand the Senate take up the measure, and they are planning a gun violence forum Tuesday “on the urgent need for Senate action” on the bill.

The three-pronged approach is aimed at pressuring Senate Majority Leader Mitch McConnell, R-Ky., to bring the House bill to the floor for a vote. Republicans have long been reluctant to back new gun control measures that might be rejected by the conservative base and are opposed by powerful gun lobby groups.

The NRA, for example, has warned the House-passed background check measure is too broad and that current background check laws need to be properly enforced.

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McConnell last week said the Senate plans to work on a bipartisan deal to address gun violence and said measures could include background checks and red flag laws, which authorize law enforcement to seize firearms from dangerous individuals.

Democrats want the Senate to take up the House-passed background check bill, which would expand background checks to all sales, including gun shows, and would ban most gun transfers and sales by unlicensed dealers.

Democrats are touting their bill as a means to close a so-called loophole that allows some gun purchases to proceed without background checks.

They argue the man accused in the most recent mass shooting in Odessa, Texas, obtained a gun through a private sale after he failed a background check at a licensed dealer.

Democrats also point to poll numbers indicating the vast majority of Americans support universal background checks.

The Senate is far more likely to ignore the House bill and take up a bipartisan background check measure authored by Sens. Joe Manchin, a West Virginia Democrat, and Pat Toomey, a Pennsylvania Republican, which would expand background checks but with broader exceptions than the House bill.

McConnell said in a recent radio interview he’s willing to take up a gun control measure that can pass Congress and win the president’s signature.

Democrats, in their letter to Trump, quoted McConnell’s pledge, which he made on the Hugh Hewitt radio program.

“Leader McConnell's statement demonstrates that Republicans in Congress are now prepared to follow you on the issue of gun safety,” Senate Minority Leader Chuck Schumer and House Speaker Nancy Pelosi wrote to Trump.

“We implore you to seize this moment when your leadership and influence over Republicans in Congress on the issue of guns is so critical.”