SANTA FE, N.M. (AP) — Democratic U.S. Sen. Tom Udall of New Mexico calls it a "pretty good guess" that he will run for re-election in 2020 without saying definitively what his plans are.

Udall on Friday stood outside a Walmart store in Santa Fe to help solicit charitable donations to the Salvation Army from holiday shoppers.

The 70-year-old senator hopes to forge compromises on legislation to expand health insurance coverage when a new Congress convenes next year with a Democratic House majority.

He hopes Republicans in the Senate majority may embrace a proposal to lower the age of Medicare eligibility to 55 for people who want to buy coverage. The current age of eligibility is 65 with limited exceptions.

Udall says expanding health insurance coverage is essential to reducing overall costs for medical care.