(CNN) High-profile Republican swing vote Sen. Susan Collins of Maine said Monday she likes to dig into the facts of a matter she is considering. That's why she said she's pushing to have a chance to call witnesses in the impeachment trial of President Donald Trump, should she feel after opening arguments they are needed.

"Obviously I would not be advocating for language to be included in the governing resolution if I did not anticipate at the end of hearing the case presented, and the q-and-a, that there might be a need for more information," said the veteran Maine senator who is working with a small group of Republicans to try to find a path forward on the issue.

A reporter noted that she had voted for witnesses during the Clinton impeachment trial and pressed for more investigations into the allegations against now Supreme Court Associate Justice Brett Kavanaugh.

"I tend to like information," she said.

Collins declined to say if the small group she's in talks with is as many as four senators, the number needed to compel testimony: "I am not going to answer that question."

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