WASHINGTON — Seeking swift action on immigration, President Barack Obama on Tuesday will try to rally public support behind his proposals for giving millions of illegal immigrants a pathway to citizenship, as well as making improvements to the legal immigration system and border security.

The president will launch his push in a campaign-style event in Las Vegas, a day after a bipartisan group of senators unveiled their own plan for addressing an issue that has languished in Washington for years.

Administration officials said Obama would largely endorse the senators' efforts, though immigration advocates said they expected the president's own proposals to be more progressive than the Senate group's plan, including a faster pathway to citizenship.