As he continues to be vetted by Mitt Romney as a possible running mate, Sen. Marco Rubio is becoming more well known across the country, according to a new poll.

The Rasmussen Reports study, which was released on Thursday, shows Rubio's poll numbers are up, especially with independent voters.

According to the poll, 42 percent of likely U.S. voters now share a favorable view of the Republican senator from Florida, while 31 percent view him unfavorably. 28 percent are undecided.

Those numbers are up since April, when 35 percent had a favorable view of Rubio while 28 percent viewed him unfavorably. 37 percent were undecided in April.

The survey of 1,000 likely voters was conducted on Tuesday and Wednesday. The margin of error is +/- 3 percentage points.