BOSTON (CBS) — The crowds at Kenmore Square fluctuated during Marathon Monday.

It was growing as the men’s and women’s wheelchair athletes came through. Then, it picked up even more as the elite runners made their descent into the city.

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Many got their early and waited.

“We always try to pick a spot where we can see each other,” said Angela Colarusso who was waiting for her husband David.

Runners headed into Kenmore Square are greeted by the crowd. (WBZ-TV)

Mom Karen Peters waited for her son.

“I want to know he’s still moving so if the tracking stops he might have fallen and gotten injured and that to me is the worst thing as a mom,” said Peters.

She’s been through this before. Her son is getting good at running marathons around the world. She said the wait is well worth it.

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“I’m going to get a wave, if I get that. But he knows I’m here and that’s all that matters,” said Peters.

Once the annual Patriots Day Red Sox game was finished the crowds grew once again.

The Beacon Street bridge over the Mass Pike is a popular and strategic spectator spot for season waiters.

“Actually this is the best spot, because if you’re tracking them you get the alert right at the 40K mark right there so it comes in and you start looking for them,” said Ryan Couto.

Couto is used to waiting for his wife Bethany. She’s run more than 70 marathons. He’s proud, but anxious because she’s not running alone. Bethany is pregnant.

“So the baby chose 26 weeks on Marathon Monday, so 26 weeks, 26 miles. Still so far so good,” he said.

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By six o’clock Monday night, the waiting was over, well, at least until next year’s Marathon.