Trump running mate contender Sen. Tom Cotton called 'a workhorse, not a show horse'

Sen. Tom Cotton, R-Ark., is in the Trump running mate spotlight.

The Army veteran, who served in combat in the Iraq and Afghanistan wars before becoming a rising star in Republican Party politics, has been viewed as a potential running mate since he endorsed the former president in early January, two weeks ahead of the Iowa caucuses.

But buzz about the senator intensified following a slew of media reports in late May that Cotton was moving up on Trump's list for the GOP's vice presidential nomination.