BANGOR — U.S. Sen. Susan Collins, who in July endorsed former Florida Gov. Jeb Bush for president only to see him bow out of the race last month, said Wednesday that she is staying neutral when it comes to remaining candidates until it’s time to vote at the national Republican convention.

“I am not going to make any further endorsement in this presidential race,” Collins said at a stop in Bangor, where she learned about clinical trials underway to treat Alzheimer’s patients. “I did endorse Jeb Bush early last summer. I was one of his earliest supporters. I campaigned twice for him in New Hampshire and I never would have guessed that he’d be out of the race so early.”

Bush ended his race for the presidency at the end of February after crushing defeats in Iowa, New Hampshire and South Carolina.

Bush decided Wednesday that he was endorsing Texas Sen. Ted Cruz for the country’s most powerful office. That did not sway Collins to follow suit.

“At this point I am going to step back and watch how the process unfolds,” Collins said. “And I do not anticipate endorsing another candidate before there is a nominee.”

She ended her comment with a joke, saying, “I was so influential last time.”

Collins is a delegate at the Republican National Convention in July in Cleveland and said she will support a candidate at that time.

Collins, who serves on the Senate Intelligence Committee, also said Americans need to stay vigilant in response to the terrorist attacks in Brussels, and emphasized the need for more intelligence sharing between the United States and western allies.

“If we are going to be successful in detecting and foiling these terrorist attacks … there needs to be a more open exchange of information,” she said. “We need to ask the moderate Muslim nations, like Jordan, to step up and do more to help combat this virulent stream of violent Islamic extremism, which is posing such a threat to our country and countries around the world.”

Collins, who was first elected to Congress in 1996, said she is very concerned, especially after learning about “linkages that have been uncovered” between the attacks in Belgium and Paris.

“In all my years in Congress, I have never been more concerned than I am now about the number and range of threats coming toward our country,” she said. “We cannot let down our guard.”

Public awareness and vigilance are keys to prevention, Collins said, stressing that, “If you see something, say something.”

“We should not live in fear but we need to be on guard,” Collins said. “If you see something that arouses suspicions, you should report it.”