CAPE ELIZABETH — Joan Benoit Samuelson is the queen of American marathon running. Or the living legend. Or choose your own platitude.

“She really is the poster child of this sport,” Deena Kastor said. “She was an enormous motivation for a lot of people.”

Which leads us to the burning question of what to call Kastor? Because while Benoit was first — and in many tangible ways remains foremost — if there’s a distance running record for U.S. women, Kastor owns it.

Benoit owned the marathon mark for 18 years before Kastor broke it in 2003. Three years later, she set a standard of 2:19.36 at the London Marathon that still stands.

As for the half-marathon and the distances of 5, 8 and 15 kilometers, no countrywoman has clocked a faster time in history than Kastor, who’s 40 and showing no signs of tapering her pace.

Kastor will make her belated debut Saturday at the 16th TD Beach to Beacon 10K, the world-renowned race Benoit has built in her hometown.

The next day, she’ll board a plane to Moscow and the IAAF World Championships, where she’ll represent Team USA in the marathon.

“It’s great preparation for Moscow next week just to get that feisty competitiveness in, and they’ve certainly collected a competitive field on the men’s and women’s side,” Kastor said. “My training’s been going great, and I’m ready to pull together a good race.”

Kastor made this same pilgrimage to Benoit’s showcase two years ago, only to be taken ill and forced to withdraw on the morning of the race.

And don’t you dare call the Beach to Beacon a tune-up.

“I’m going to run for my life tomorrow,” Kastor said.

Good strategy, because given the caliber of the field, it’s either that or be an also-ran.

The women’s field includes recent winners Lineth Chepkurui of Kenya, who set the course record of 30:59 in 2010, and Aheza Kiros of Ethiopia (2011). And another Ethiopian, Sule Utura, might be the favorite after winning the Quad City Times Bix 7 in Iowa one week ago.

“It’s a hot competition. There’s no doubt about it. Larry (Barthlow, Beach to Beacon elite athlete coordinator) was rattling off all these statistics and I was like, ‘Aw, one more?’ I’m over here counting what place I’m going to be in,” Kastor said with a laugh. “But no, it’s competitions like this that bring out the best in people. You never want to dodge the competition.”

Kastor brought home the bronze medal from the 2004 Olympic Games in Athens. She joined 1984 gold medalist Benoit as the only U.S. women to win a spot on the podium.

Her titles in the 2005 Chicago and 2006 London marathons had her poised for another Olympic run. Kastor won the 2008 U.S. trial in Boston but was forced from the race in Beijing with a foot injury.

Motherhood has moved to the forefront in Kastor’s life — she and husband Andrew welcomed a daughter, Piper Bloom, in February 2011. But this year’s milestone birthday has been accompanied by a career resurgence. Kastor was third in the Los Angeles Marathon in March.

“My best world championships finish is sixth place, so I’d love to be able to get in the top five in Moscow,” Kastor said. “My training has been great. I’ve looked at the competition and feel if I’m engaged enough on that day and hungry enough that I can do that.”

Kastor, born in Waltham, Mass., was 11 and growing up in Agoura Hills, Calif., when she sat in front of her television and watched Benoit win the inaugural Olympic marathon, only 40 minutes away in Los Angeles.

“I don’t think it’s any coincidence that I became a runner a year later,” she said.

An eight-time All-American at the University of Arkansas and an eight-time national champion in cross country, Kastor also followed her idol’s lead into the toughest test and longest distance of all.

But she still feels her closest connection to shorter, community road races such as the Beach to Beacon, she said.

“It’s such an equalizer. You realize you have so much in common with the general public, that we’re all in it to better our times or to lose a couple pounds or whatever the motivation is,” Kastor said. “We all have that as our carrot to keep us moving forward one step at a time.

“For 16 years this race has been drawing on some of the best athletes around the world,” she added. “It’s great to have that opportunity to get the best out of yourself when you’re competing against the best. So it’s that, but it’s also the buzz and support of what this race embodies. It’s a small-town race with a global feel to it. It’s a pretty amazing combination to be able to pull that off.”

Only a living legend could do it.

With an assist from that rare person who can rival her accomplishments.

koakes@sunjournal.com