WASHINGTON — One House bill, backed mostly by Republicans, would repeal a tax imposed on some medical devices to help pay for President Barack Obama’s health care law, a statute they despise. With another, still a bare-bones outline, the GOP would make last year’s $1.5 trillion tax cut permanent and expand reductions for families, homeschooling and businesses.

House Democrats have a plan for helping students afford the growing costs of college, in part by creating a partnership with states to provide two years of tuition-free community college. It would also expand the size of Pell Grants, which largely go to undergraduates from lower-earning families.

Lawmakers promoted each of these proposals Tuesday, though none seems likely to become law soon. But they typify a time-sensitive priority for both parties: honing their messages for elections, just over 100 days away, in which congressional control is the prize.

The House starts summer recess at week’s end, and lawmakers need arguments to take home for town halls and campaign advertising and to rev up voters and contributors. Democrats need to gain 23 seats in November’s midterms to capture House control, which is widely seen as doable, so both parties are producing bills to shore up political weak spots or play offense.

For House Speaker Paul Ryan, R-Wis., who is retiring, that meant giving Republicans credit for the strengthening economy and using Democrats as a foil, perhaps offering a GOP playbook for fall campaigns.

“They’ve scoffed at Americans who’ve benefited from more money in their paychecks,” he told reporters, a reference to House Minority Leader Nancy Pelosi’s comparison of GOP tax cuts for the wealthy to the “crumbs” that went to lower earners. “They’re determined to erase this progress. Even more, they want to take this country to a dramatically different place, to the far left.”